How To Flush A Water Heater Like A Pro

How often do you think about maintaining your water heater? Like most people, we’re willing to bet, not much. After all, your water heater is usually tucked away somewhere like a basement or garage. So why would you think about maintaining it regularly when it’s out of sight and mind? We’re here to teach you how to do one of the most important water heater maintenance tasks there is. Keep reading to find out how to flush a water heater like a pro. It’s sure to keep your heater clean and running in tip-top shape. 

When Should I Flush Out My Water Heater? 

Look, there aren’t any hard, fast rules on when you should flush out your heater. We suggest setting up a maintenance schedule. If it’s on the calendar, you’ll definitely remember to do it. Even if the heater is probably clean, there’s no harm in flushing it out. 

As a good rule of thumb, flushing it out every one to three years is a good schedule to have. You should flush it out every year just to make sure everything is in good working condition. 

Getting Started

You probably know what kind of heater you have. Whichever it is, please make sure to turn off the power supply. If it’s electricity, cut off the breaker. For gas, you will cut off the gas line to the water heater. This is probably one of the most important steps to make sure no accidents or injuries occur, so don’t forget!

Step 1: Cut Off The Thermostat

Gas water heaters have a thermostat that’s often toward the bottom of the water tank. You can turn the thermostat to pilot, but we suggest playing it safe and cut the thermostat off completely. On older heaters, this may mean you will have to light your pilot light again. 

For electric heaters, cutting off the power will get the job done. 

Step 2: Use Up All The Hot Water

Once you have all the power or gas turned off, you need to get ready to empty the heater. First, make sure to turn off the cold water valve that leads to the heater. Once that’s done, turn on some hot water faucets in the house (this will prevent a void from forming in the lines as you flush the system). 

Step 3: Open The Heater’s Pressure Relief Valve

If you open the pressure relief valve, this will help drain water from the heater more efficiently. Also, by opening the valve, you can see if it’s operating properly. Before you do this, though, please make sure you have a basin or bucket under the drainpipe to catch the water that will come out. Watch out, too. The water that comes out is usually pretty hot!

Once the valve has released all the pressure, just let the water in the tank cool. 

Step 4: Hook The Heater Up To A Hose

Finally! The water inside has cooled off. You’re ready to drain the heater. Before you turn on that valve, hook it up to a hose. Once the other end of the hose is either outside in the grass or inside a bucket, open the valve all the way.

Continue to drain the tank until it is completely empty. Watch how much sediment, mineral deposits, and gunk come out of there. It’s impressive. 

Step 5: Flush The Tank Out

After all that dirty water empties out of the tank, you’ll want to flush it all clean. Turn on the cold water valve that you shut off at the beginning, and let it run for as long as it takes the water to come out clean. 


Wrapping Everything Up

Now that you know the water coming out of your heater is clean, and everything is working smoothly, it’s time to put everything back together. Make sure to close the pressure relief valve, turn off the faucets you had running, and let the tank fill up. Once the tank is filled, open the pressure relief valve again to clear out any air. Turn a hot water faucet to ensure there are no air bubbles in the lines. Finally, turn the breaker and thermostat back on, or the gas, and you’re good to go! 

Since you know how to flush a water heater now, don’t forget to add this to your calendar for next year! 

If you’re a more visual person, we’ve included a link to a video tutorial on how to flush your water heater.


Looking To Replace Your Old Water Heater?

Call Autry Plumbing in Asheville, NC for all of your plumbing needs. We’ll get you on a maintenance schedule that protects your investment for years to come.